29 Dec
2012
29 Dec
'12
5:27 p.m.
Hello!
I'm going to just make this response public just so that everyone can
know more about the system that I've got my hands on.
Plus for any one morbidly curious there's also the story of what
happened to my previous '11 system...
On 29 December 2012 18:44, Jerome H. Fine <jhfinedp3k at compsys.to> wrote:
In the past, I have placed an M8190-AB into the
backplane for a VT103
which is a non-PMI serpentine 4 * 4 (four double dual slots serpentine) Qbus
Hmm,
that I should remember if I can get another quad wide CPU, I've a
VT-103 and it's currently running on a "puny" 11/23. Though, isn't the
VT-103 backplane only Q18 not Q22? (Is it a wirewrap backplane? Or can
an upgrade to Q22 be done easily, if it isn't?)
backplane. I have also placed that M8190-AB into a
BA23 in the third slot
position with 2 * 2MB PMI boards in slots 1 and 2. The 3 board
configuration
is reported by RT-11 as a PDP-11/83 with PMI memory. The system is also
about 20% faster than if the 2 PMI boards are placed in slots 2 and 3 and
the
An interesting thing is I seem to recall that if you use the dual wide
J-11 processor in a machine it's an 11/73, if you use a quad-wide J-11
-- that isn't the 11/53 -- with PMI RAM behind the CPU on the
backplane, it's an 11/83 or 11/93. Stick that same memory in front of
the CPU, or use only QBUS memories and it becomes an 11/73B.
Some one else can check if I got that fact right.
So the quick answer is probably that all M8190 boards
are PMI capable, but
the PMI is not activated if PMI memory is not present in the correct
slot(s).
In addition, probably all M8190 boards are happy being placed into a VT103
backplane which will not support PMI activation.
That's basically the crux of my question. I don't really need/want PMI
memory, as the backplane I have doesn't support PMI as it's all Q22
ABAB.
Why are you reverting to a dual board without the boot
ROMs? I have
tested a VT103 (22 bit upgraded) with an M8190-AB board and one
4 MB quad memory board (obviously non-PMI memory) in the second slot..
It worked very well and no magic smoke was released. The other two
The
"downgrade" is because if the KDJ11-BF won't play nice on an ABAB
backplane the KDJ11-AC + (22-bit capable) BDV11 will.
ABAB slots had a Quad ESDI controller and a DHV11. It
was a great
demo system. Obviously the three 600 MB ESDI drives had to be
placed outside the VT103 on a separate power supply and I added
a fan for each drive as well. Running RT-11 with 600 MB hard drives
is enjoyable since there is ample space for files. If the VM: device
driver is used as the system disk, it is even possible to power down
the ESDI drives, replace one or more of the ESDI drives, then power
the ESDI drives back up. You can then UNLOAD and then LOAD
the MSCP device driver and just continue without losing anything,
although I would ALWAYS close all files on all of the EDSI hard
drives first, just as you would if you were using any other replaceable
media such as an RX50 or an RX02 floppy diskette.
I *WANT* your VT-103. So much. Mine is a rather less impressive
system, only a KDF11-AB (if I remember that;s the designation of the
one with an MMU but no FPP), and NatSemi 256KB RAM board, a
DLV11-J/DLVJ1-M and a 18-bit only BDV11. No internal TU58.
Which Qbus backplane with only ABAB serpentine slots
do you have?
An H9275A, Q22 bus, not Q18. It's the 4x9 that'll fit into a BA11-N
box. If I remember correctly, the 11/23+ version of the BA11-N box
comes with that one in it by default. Though, my box is a PDP-11/03
box that got upgraded.
As a complete tangent I also have an H9273A backplane (4x9 backplane
that fits in a BA11-N box, Q18 ABCD all the way down) that isn't doing
anything...
I do have an M8192-YB which would require adding the
Floating point chip.
Actually, I got an offer of a KDJ11-AC (M8192-YC) for my KDJ11-BF. So
I'm not losing much more beyond a few MHz of clock. Same individual
also has a 22-bit capable BDV11 so that won't be much of a problem.
This is especially nice since the BA11- box the backplane -- and
system -- live in has a pair of clip things to prevent the bottom card
in the backplane from being removed, which I don't want to faff about
with so I'll just stick the BDV11 in there, as bus termination is a
good thing.
Assuming that you can use the M8190-AE, you can skip
the BDV11. The 4 MB
of memory should not be too difficult to find. More memory is always
helpful.
How many slots does you backplane have? Can you find a BA23 box instead
and use the PMI memory? With 8 quad slots, you will have no problems with
all
of those boards.
My backplane is 4 by 9. So more space then the BA23 though, not PMI capable.
Nope, I can't get my hands on a BA23 box. And I have no wish to get a
BA23 box (though I do like how you can stick a hard disk/RX50/MSCP
cartridge tape into its two front slots), plus it would look just a
bit "off" (read: ugly) having the beige BA23 the lovely -- very white
-- DEC short rack I got my hands on that has the --equally very white
-- BA11-N box in it. Especially since both the rack and the box are a
PDP-11/03-L rack, with associated, matching bevels/faceplates.
You probably will not forget what you imply you did
that makes a
replacement necessary. I remember the ":forgetful" moment that I
had many years ago with two RD52 drives in a BA23 box when
both has the DS3 set. I lost the contents of both drives.
Yes, I'm never again letting the machine out of my sight or leaving
the house without Crazy Psycho Bitch Lady With No Respect For Personal
Property in tow, and/or the machine and rack bolted to the floor,
wall, and any available fixed surface. Because *I* didn't do anything
to lose my entire PDP-11 system beyond living at my university dorm.
CPBLWNRFPP did something to my system and it is out of my possession
without any way for me to get it back -- and she can't give me a
straight story as to whether she threw the machine out, or sold it.
Personally since she has no idea what the machine was other then an --
in her words -- "old, dirty, fucking computer" I think she carted it
to the dump and tossed it. Oh and it was *FAR* from dirty as I made
sure to keep it spotless (the all white bevel/faceplate drove me nuts
as it seemed to attract dust from everywhere in a three light year
radius... just like my piano).
It *really* pissed me off as I had amassed a nice collection of cards
-- thank you to who sent me those, you know who you are and I am
eternally grateful to you -- which was quite impressive, if I had a
bit more RAM and backplanes I could've built another two or three '11
systems and still had cards left over! Also, I had a nice collection
of software on 8" diskette which I'm probably never going to be able
to replace -- and some of which was probably unobtanium, which I never
got a chance to try and image because, as mentioned, living in a
university dorm; neither did I have it catalogued as again,
university. I also had a nice collection of peripherals, namely a
quite rare -- since I've not seen another -- DSD-880/8 combination of
8" DSDD capable diskette drive and 8MB drive that pretended to be a
slightly crippled RL02. There was also an RX50, but I never got a
chance to use it...
Oh and I shouldn't forget to mention that I got a majority of the
system *for free* as gifts and trades with others. I especially like
the fact I got a CQD-220A/TM for a steal of only $150.00, and now I'm
probably going to be paying out the nose to replace just that card.
Thank Christ my VT-103 was somewhere else -- sitting on a shelf in my
old high school on a long-term loan because aforementioned CPBLWNRFPP
had a conniption when I got it and I did not want to see it get tossed
in the trash, nor did I have any time to put it anywhere better.
Oh look, I'm ranting. I'm going to cut this off before the swearing starts.
Please let us know what the answer is if you hear
privately!
Jerome Fine
I still haven't heard an authoritative answer one way or another --
beyond yours of course -- as to whether or not I can put the PMI
processor in the non-PMI backplane, so I'll keep holding out. Or just
trade it, as I don't mind the slight downgrade in performance.
Cheers,
Christian